Article handling apparatus



I Aug. 2, 1966 E. A. VERRINDER ET AL 3,263,829

ARTICLE HANDLING APPARATUS Original Filed July 8. 1960 5 Sheecs-Sheet 1F Il3 1 2 I56 I 65 Ac I55 55 FIE'|| 2 97 26 INVENTORS ERNEST A.VERRINDER DONALD o. DERRICOTT BYW ATTORNEY Aug. 2, 1966 E. A. VERRINDERET AL 3,263,829

ARTICLE HANDLING APPARATUS Original Filed July 8. 1960 5 Sheets-Sheet 8INVENTORS ERNEST A. VERRINDER DONALD D. DERRIOOTT svbww/W ATTORNEY Aug.2, 1966 E. A. VERRlNDER ET 3,263,329

ARTICLE HANDLING APPARATUS Original Filed July 8. 1960 beets-Sheet 3INVENTORS w ERNEST A. VERRINDER DONALD D. DERRICOTT BY W ATTORNEY UnitedStates Patent 3,263,829 ARTICLE HANDLING APPARATUS Ernest A. Verrinder,Riverside, Calif., and Donald D.

Derricott, Cincinnati, Ohio, assignors to FMC Corporation, San Jose,Calif., a corporation of Delaware Continuation of application Ser. No.41,533, July 8, 1960.

This application Get. 28, 1963, Ser. No. 320,256

14 Claims. (Cl. 214-85) This invention pertains to article handlingapparatus, and more particularly relates to apparatus for removingarticles from a pallet.

This application is a continuation of the application of Ernest A.Verrinder and Donald D. Derricott, Serial No. 41,533, filed July 8,1960, now abandoned.

An object of the present invention is to provide an improved method ofdisassembling articles from a pallet load of articles.

Another object is to provide an apparatus that will remove articles froma pallet more efliciently than has heretofore been possible.

Another object is to provide an article handling apparatus made up ofvery simple mechanisms that provide an inexpensive compact unit.

Another object is to provide an improved carriage for stripping articlesfrom a pallet load of articles.

Another object is to provide an efficient drive mechanism for a carriageof a pallet unloading machine.

Another object is to provide an improved pallet handling mechanism.

Another object is to provide improved conveying means for an articlehandling machine.

Another object is to provide an improved control system for adepalletizing machine.

Other and further objects and advantages of the present invention willbecome apparent from the following description taken in connection withthe accompanying drawings.

FIGURE 1 is a more or less diagrammatic plan view, partly broken away,of the machine of the present invention, showing one position of themechanism during a pallet unloading operation.

FIGURE 2 is a diagrammatic side elevation of the machine of FIGURE 1.

FIGURE 3 is an enlarged fragmentary diagrammatic perspective of aportion of the machine of FIGURE 1.

FIGURE 4 is an enlarged vertical section taken on line 4-4 of "FIGURE 3.

FIGURE 5 is an enlarged fragmentary diagrammatic perspective of theupper portion of the machine of FIG- URE 1.

FIGURES 6 and 7 are schematic perspectives of portions of the drivemechanism of the machine of FIG- URE 1.

FIGURE 8 is a diagrammatic perspective showing the location of themotors and electrical control switches used during a depalletizingoperation.

FIGURE 9 is a diagram of the electrical control circuit used to carryout a pallet unloading operation.

FIGURES 1014 are diagrammatic operationl views showing consecutive stepsin a pallet unloading operation.

The embodiment of the depalletizing machine of the present inventionshown in FIGURES 1 and 2 comprises, in general, a frame supportstructure having a base 26, a plurality :of spaced vertical posts 27,and an upper support frame 28. A pallet feed conveyor C is provided inthe base 26 in the form of a plurality of rollers 32 that areinterconnected in mutual driving relation by a sprocket and chain drive(not shown) that is operatively connected to the ends of severalrollers. The rollers are driven by a motor M5 (FIG. 1) through asprocket and chain drive 35 that is connected to the end roller 32a ofthe conveyor.

3,263,829 Patented August 2, 1966 When a loaded pallet is deposited, asby means of a fork lift truck, on the pallet conveyor C, and the motorM5 is energized, the loaded pallet is moved into the machine in thedirection indicated by reference arrow 37. The pallet will be advancedto a position above an elevator table T, which at that time will be in alowered position below the surface of the conveying rollers 32. When theloaded pallet is in position, the table T is moved upwardly until theuppermost layer of articles is positioned a short distance above theupper frame 28, as indicated by layer L in FIG. 2. As seen in FIG. 1, alayer of articles consists of several transverse rows R1, R2, R3 and R4.A flexible, article-stripper or transfer carriage TC (FIGS. 2 and 3), inthe form of a plurality of interconnected transverse stripper rollers 40(FIGS. 3 and 5) is moved toward the left (FIG. 2) to successively engagethe articles row by row, lift the articles and transfer each row to anaccumulator carriage AC which delivers each row to a diverter conveyorDC (FIG. 1) for movement laterally off the machine in the direction ofarrow 42 to a suitable take-away conveyor (not shown).

The elevator table T comprises a grid-like support plate 48 (FIG. 3),the transverse bars of which are adapted to be disposed between adjacentrollers 32 of the pallet conveyor when the table is in its lowermostposition. A rigid post 50 is secured to each bar 51 of the grid 48 andprojects upwardly therefrom. Each post 50 is disposed in a guide slot53, the slots 53 on one side of the machine being formed by two spacedvertical angle'bars 54 that are part of the support structure of themachine, and the slot 53 on the other side being formed by two verticalbars 55. A lifting chain 58 is secured to the upper end of each post 50,and each chain is trained around a sprocket 60 that is keyed to a shaft62 rotatably journalled in the support structure. A reversible motor M1drives shaft 62 through a belt and pulley drive 65, an idler shaft 66, agear 67 keyed to shaft 66 and a gear 68 that is in mesh with gear 67 andkeyed to shaft 62. A counterweight 69 is secured to the end of eachchain 58.

The stripper or transfer carriage TC comprises the several elongatedparallel cylindrical rollers 40, each of which is secured at itsopposite ends to chains 81 and 82 (FIGS. 5 and 6) by means of pins 83that are connected to the chain links. The rollers 40 are provided withfriction surfaces such as a rubber covering or tape so that the rollerswill effectively grip the articles. Each of the chains 81 and 82 istrained over a sprocket 85 (FIG. 6) that is freely journalled on atransverse shaft 86 rotatably mounted in suitable bearings in the uppersupport frame 28. Each chain is also trained around a sprocket 88 (FIG.5) that is keyed to a forward transverse rotary drive shaft 90. A bar 91(FIG. 3) is connected between the rearward end of the chains, and eachend of the bar is slidably disposed in a slot 92 formed by two verticalangle bars 27 of the support structure of the machine.

The transfer carriage TC is moved from its rearward position shown inFIG. 5, toward the forward end FE of the machine by means of a tensionspring unit 95 (FIGS. 2 and 7) that is made up of a plurality of springs96 connected at one end to a plate 97 that is fixed to the stationarybase 26, and connected at the other end to a bar 98. A chain 100, whichis secured to the bar 98, is trained around a sprocket 101 (FIG. 7) thatis keyed to the forward drive shaft 90. A counterweight 103 is securedto the free end of chain 100.

The transfer carriage is moved to the rearward position shown in FIG. 5by means of a second transverse drive shaft which is parallel to driveshaft 90 and is journalled in the upper frame 28. This second driveshaft 110 is driven by two V-belts 112 and 113, each of said belts beingtrained around a pulley 115 keyed to shaft 110 and around a drive pulley116 keyed to the shaft 86. The shaft 3 86 is driven by a reversiblemotor M2 through a chain and sprocket mechanism 114 that is connected tothe motor drive shaft 117. Accordingly, when the motor shaft 117 isrotated, the shaft 86 drives the shaft 110 through the two V-belts 112and 113.

A one-direction clutch 120 (FIG. 7) is mounted on the shaft 110 and isso arranged that, when shaft 110 is rotated clockwise, it will driveshaft 90 clockwise through a chain 121 that is trained over a sprocket122 keyed to shaft 90 and over a sprocket 123 secured to the clutch 120.When the shaft 110 is rotated counterclockwise, the clutch 120 willoverrun and will not drive the sprocket 121. It is to be noted that,when the spring unit 95 exerts a downward pull on chain 100 and rotatesthe shaft 90 counterclockwise to move the transfer carriage to theforward end of the machine, the sprocket 122 will drive the chain 121while sprocket 123 overruns on the shaft 110. Accordingly, the carriageTC, which is carried by chains 81 and 82, is moved forwardly only by thespring unit 95, and is moved rearwardly by the drive shaft 110 drivingthrough clutch 120.

The V-belts 112 and 113 not only drive the shaft 110 but they alsofrictionally engage the undersurface of the transverse rollers 40 of thetransfer carriage to rotate the rollers.

The drive arrangement is such that, when the transfer carriage TC isbeing moved toward the forward end of the machine by the spring unit 95,the shafts 86 and 110 are driven counterclockwise, causing the upper runof the V-belts to be moved toward the forward end of the machine. Thecarriage TC is moved bodily forward at about the same linear speed asthe upper run of the V- belts. Accordingly, when the leading rollerengages the first article and the forward movement of the carriage ismomentarily stopped, the upper runs of the V-belts begin to move fasterthan the carriage and the rollers 40 are rotated clockwise by theV-belts during the remainder of the time they are carried toward theforward end of the machine. Also, when the carriage is moved toward therear of the machine due to clockwise rotation of shaft 110, shafts 90and 86 are rotated clockwise, and the upper runs of the belts 112 and113 are moved toward the rear of the machine at about the same linearspeed as the carriage.

The forwardmost of the rollers 40 is designated as 40A (FIG. Roller 40Ais not frictionally driven by V- belts but is positively driven fromshaft 110 through a chain 130 trained around a sprocket 131 keyed toshaft 110 and a sprocket 132 keyed to a shaft 133 that is rotatable inframe 28. A second chain 135, which is trained around a sprocket 137keyed to shaft 133, is in driving engagement with a sprocket 138 keyedto the roller 40A. Thus, when shaft 110 is driven counterclockwiseduring the forward movement of the carriage TC, the upper run of thechain 135 is moved toward the forward end of the machine to positivelydrive roller 40A in a clockwise direction. Similarly, when shaft 110 isrotated clockwise during rearward movement of the carriage TC, the upperrun of the chain 135 is moved rearward ly and tends to positively driveroller 40A in a counterclockwise direction. However, since the carriageTC is carrying the roller 40A bodily in the same direction as the chain135 at about the same speed as the chain, the counterclockwise rotationof the roller is very small and does not materially retard the rearwardmovement of the article as it is transported rearwardly by the carriage.

The accumulator conveyor AC comprises a plurality of transverse rollers140 that are rotatably journalled in the upper frame 28 and are rotatedby two V-belts 142 and 143 (FIG. 1) which frictionally engage theunderside of the rollers. Each belt is trained around a pulley 144 thatis freely rotatable on shaft 86 and around a pulley 145 that is keyed ona transverse shaft 147 mounted on the rear end of the machine. A motorM3 (FIGS; 1 and 2) drives the shaft 147 through a belt 149. The

motor M3 is a reversible motor which is driven in one direction duringdepalletizing and in the opposite direction during palletizing.

The diverter conveyor DC comprises a pair of spaced parallel chains 150and 151 (FIG. 1) that extend transversely across the rear end of themachine. Each chain is trained over a sprocket 155 journalled on a shortshaft 156, and around a sprocket 157 keyed to a shaft 158 (FIG. 5) thatis driven by a motor M4 through a belt 162. The motor M4 is also areversible motor which is driven in one direction during depalletizingand in an opposite direction during'palletizing. A plurality of pusherbars 164 are secured to the parallel chains 150 and 151. The upper runsof the chains 150 and 151 are disposed below the surface of the rollers140 of the accumulator conveyor AC while the pusher bars are disposedabove the rollers. Accordingly, when a row of articles is moved to aposition against a guide bar 165 above the chains 150 and 151, the nextpusher bar 164 on the chains will engage the row of articles and pushthem in the direction of ar-, row 42 out of the machine. A pair oflarge, rubber covered rollers 167 are keyed to the shaft 158 and act asaccelerator rollers causing separation of the articles of the row asthey are moved out of the machine.

In FIGURES the switches of the electrical control circuit employed withthe depalletizer are diagrammatically shown. Switch LS1 is mounted on astationary bracket 200 (FIG. 5) that is secured to the frame 28 above atransverse stop plate 205 near the forward end of the machine. Anactuator 201 is pivotally mounted by a removable pivot pin 206 on an arm207 projecting from the stop plate 205. The actuator is disposed in anotch 205a in the plate 205 and has an arm 202 at one end arranged toengage the switch arm 203. At its other end, the actuator 201 has acylindrical member 204 arranged to be contacted by an article in row R4of the uppermost layer of articles on the table T as seen in FIG. 2.When the article moves the member 204 upwardly, the switch arm 203 isactuated to de-energize the motor M1 which causes the elevation of thetable.

Switch LS2 (FIGS. 3 and 8) is mounted on the frame 28 and has a switcharm 210 overlying an opening 211 in the frame. When the table T has beenraised to the level at which the last layer of articles is in positionto be removed from the pallet on the table T, an arm 213 (FIG. 3)projecting upwardly from the table engages the switch arm 210 to actuatethe switch LS2 to partially close a circuit which, when energized, willcause the shaft of the motor M1 to be rotated in a direction to lowerthe table.

Switch LS3 is mounted on the outer side of the vertical angle bars 54(FIG. 3) and has a switch arm 215 that is positioned to be contacted bya lug 1214 on the upstanding rod 50 on that side of the table T duringdownward movement of the table. When switch LS3 is actuated by the lug214, the downward movement of the table is stopped. Switch LS4 ismounted on the outer side of one of the vertical posts 27 and has aswitch arm 217 projecting into the guide slot 92 in the path of movementof bar 91 at the rear end of the article transfer carriage TC. Theswitch LS4 is so positioned that, when the carriage has reached itsforwardmost position, the bar 91 actuates the switch LS4 to de-energizethe coils of motor M2 which causes the rotation of the motor drive shaftin the direction efiecting forward movement of the upper runs of belts112 and 113 during movement of the carriage to the forward end of themachine.

Switch LS5 is mounted directly below switch LS4 and has an actuator 218arranged to be engaged by the bar 91 of the carriage when the carriagehas reached its rearmost position after stripping a layer of articlesfrom the pallet on table T.

Switch LS6 (FIGS. 3 and 4) is mounted on a post 227 projecting upwardlyfrom the frame 28 near the rear end of the machine. The switch LS6 hasan arm 222 arranged to be engaged by an upper arm 223a of an actuator223 that is setscrewed to a transverse shaft 225. A lower arm 223b ofactuator 223 engages a stop pin 226 on the post 227. Anarticle-intercepting plate 228 (FIG. 3), which overlies the centralportion of the accumulator conveyor AC, is removably secured to thetransverse shaft 225 by setscrews 230 and exerts a turning force on theshaft to rotate the shaft and move the lower arm 2 231) of actuator 223against stop pin 226 and move the upper arm 223a out of contact with theswitch arm 222. When a row of articles passes from the accumulatorconveyor to the diverter conveyor, one of the articles engages the plate228 and pivots the shaft 225 counterclockwise (FIG. 3) caus ing theactuator arm 223a to engage and actuate the switch arm 222. When theswitch LS6 is thus actuated, the motor M3 which drives the live rollersof the accumulator conveyor is de-energized and the motor M4, thatdrives the chains of the diverter conveyor, is energized.

Switch LS7 (FIGS. 5 and 8) is mounted on the guide bar '165 which issecured in fixed position across the rear end of the machine. The switchhas a curved arm 241 arranged to be engaged by each pusher bar 164 ofthe diverter conveyor DC as the plate comes upwardly around the end ofthe conveyor. The switch LS7 is so located that, when the curved arm 241is engaged by a pusher bar, that bar has not yet reached a position inthe path of a row of articles being advanced on the accumulatorconveyor. Thus, when the switch arm 241 is actuated, the diverterconveyor motor M4 is de-energized and a pusher bar 164 is stopped in aposition such that the next row of articles can be moved onto thediverter conveyor in front of the bar. Then, when the diverter conveyoris started again, that pusher bar will engage and push the row ofarticles from the machine.

Switch LS9 (FIGS. 3 and 8) is mounted on a cross bar 245 of the supportstructure base 26 adjacent the rear end of the table T, when the tableis in its lowered position. The switch has an arm 247 arranged to beengaged by a loaded pallet as the pallet is brought into the machine.When switch arm 247 is actuated, the motor M5 that drives the palletsupply conveyor C is de-energized, and the coils that cause the shaft ofthe motor M1 to be rotated in a direction to raise table T, areenergized.

Switch LS10 (FIGS. 3 and 8) is mounted on a post 249 projecting up fromthe upper frame 28 adjacent switch LS6. An actuator 250 of switch LS10is arranged to be engaged by an upper arm 252a of an actuator 252 thatis setscrewed to a transverse rotary shaft 254. A contact plate 256,that overlies the accumulator conveyor, is secured by setscrews 257 toshaft 254 and, due to its weight, tends to rotate the shaft clockwise(FIG. 3) to move a lower arm 252b against a fixed lstop rpin 258. Whenan article of an advancing row of articles engages the plate 256, theshaft 254 is rotated counterclockwise and the switch arm 250 is actuatedby the ac tuator upper arm 252a to open switch LS10. If a row ofarticles is still on the diverter conveyor, motor M3 will bede-energized and the accumulator conveyor roller will be stopped so thatthe row of articles on the accumulator will not be moved onto thediverter conveyor while a previous row is still being moved laterally bythat conveyor.

A complete cycle of the depalletizing operation will be explained inconnection with the electrical control diagram of FIGURE 9 and theschematic operational views of FIGS. 1014. In FIG. 9, the lines L1, L2indicate a source of 110 volt A.C., 60 cycle electricity. At thebeginning of a depalletizing operation, the transfer carriage TC, whichacts as a stripper during a depalletizing operation, is at the rear ofthe machine in engagement with switch LS5 holding contact LS5-1 incircuit 3 closed and holding LS5-2 contact in circuit 10 open. Also, atthis time, the table is in its lowered position holding open contactLS3-1 in circuit 5 and closing contact LS3-2 in circuit 7. Further, oneof the lugs 164 on the diverter conveyor is holding contact LS7-'1 inthe circuit 14 open to de-energize the diverter conveyor motor M4. Tostart the operation, the start button in circuit 1 is momentarily closedto energize relay A in circuit 2 and cause relay contact A1 in circuit2, A2 in circuit 8, and A3 in circuit 12 to close. Since contact LS3-2in circuit 7 is closed, the pallet conveyor motor M5 will be energized.Also, the live roll accumulator conveyor motor M3 in circuit 12 will beenergized. A loaded pallet is brought in on the pallet conveyor andengages and closes contact LS9-1 of switch LS9 in circuit 15 to energizethe relay B which is locked in through contact B2. Contact B3 in circuit7 opens to de-energize the pallet conveyor motor M5. Contact B1 incircuit 3 closes to energize the raise magnetic Ml-RAISE of motor M1causing the elevator to move upwardly and raise the table. Contact M'l-Rin circuit 5 opens to prevent actuation of the lower magnetic duringupward movement of the elevator. As the table moves away from switchLS3, contact LS3-1 in circuit 5 closes and contact LS3-2 in circuit 7opens. An article on the top layer L (FIG. 10) of the load engagesswitch LS1 and opens contact LS1-1 in circuit 3 to de-energize the raisemagnetic M1-RAISE of motor M1 to stop the table in the predetermineddesirable position for depalletizing.

Also, contact LS1-2 in circuit 8 is closed to energize the magneticM2-STRIP of motor M2 which drives the shaft counterclockwise and movesthe upper runs of V-belts '112 and 113 forwardly as the carriage TC ismoved forward by the spring unit 95. Contact M2-S in circuit 10 opens toprevent the energizing of the return coil during forward movement of thecarriage. The magnetic M2STRIP is locked in through M2S in circuit 9. Asthe stripper carriage moves forward, switch LS5 is permitted to returnto its normal condition, causing contact LS5-1 in circuit 3 to open andcontact LS5-2 in cir. cuit 10 to close.

As the carriage TC moves forwardly, its leading roller 40A is rotatedclockwise by the shaft 110 and the trailing rollers 40 are rotatedclockwise (FIG. 10) as soon as they come into engagement with theforwardly moving runsof V-belts 112 and 113 and the carriage engages theleading article of the layer. When the leading roller 40A engages thefirst row R1 of articles, the friction surface of the roller lifts upthe articles and moves the articles to its upper surface. As the forwardmovement of the carriage continues, the roller 40A lifts up each row ofarticles in turn, as shown in FIGS. 11-14, and moves the articlesrearwardly over the trailing rollers 40, which are of course alsorotating clockwise. Each row of articles is thus carried rearwardly, insubstantially equally spaced relation to adjacent rows, and isdepositjadcon the live rollers of the accumulator conveyor In FIG. 10,at the right side of the accumulator AC, the rows R1R4 are shown inphantom lines in the positrons they assume on this conveyor as theyapproach the diverter conveyor DC.

When the stripper separates the first row of articles of the layer awayfrom the row next behind, this first row is carried rearwardly andengages plate 256 to open switch LS10. No control operation occurs andthis first row passes on to the diverter conveyor where it engages andmoves plate 228 to open contacts LS6-1 in circuit 8. Contact LS6-2 incircuit 12 is opened to tie-energize the accumulator conveyor motor M3,and contact LS6-3 in circuit 13 is closed to energize motor M4 of thediverter conveyor. When the motor M4 is energized, the lug of theconveyor starts to sweep the first row of articles out of the diverterconveyor.

In order to maintain a desired spacing between successive rows ofarticles on the accumulator conveyor, it is necessary to stop thestripper rollers when the accumulator is stopped. Accordingly, the rowof articles following the row on the diverter will engage plate 256 andopen the contact LS10-1 of switch L510 in circuit 10 to deenergize themotor magnetic MZ-STRIP and stop the belts which rotate the stripperrollers. When the first row is clear of plate 228 contact LS6-1 incircuit 8 closes to re-energize motor magnetic M2-STRIP and start thestripping operation of the stripper again. Contact LS62 in circuit 12closes to energize motor M3 and once more start the accumulator liveroll conveyor. Contact LS6-3 in circuit 13 opens and, when the first rowof articles has cleared the diverter conveyor, one of the lugs on thediverter conveyor engages and opens the switch contact LS7-1 in circuit14 to de-energize motor M4 to stop the diverter conveyor. 1

The second row R2 now enters the diverter conveyor and engages plate 228to open contact LS6-l in circuit 8, open contact LS6-2 in circuit 12 tode-energize motor M3 of the live roll conveyor AC, and close contactLS6-3 in circuit 13 to energize motor M4 of the diverter conveyor. In apreferred arrangement, the speed of the various conveyors and thestripper carriage are so chosen that the diverter conveyor willdischarge the row of articles thereon before the next row contacts plate256.

When all of the rows of boxes of a particular layer have been directedrearwardly, the stripper carriage ar rives at the forward end of itsstroke and opens Contact LS4-2 of switch LS4 in circuit 8 to de-energizethe mag netic M2STRIP and stop the rotation of the rollers of thestripper carriage. Contact LS43 in circuit 10 is closed to energize themotor magnetic MZ-RETURN that causes the rearward movement of thestripper carriage. Contact M2-R in circuit 8 opens to prevent theenergizing of the strip magnetic during rearward movement of thecarriage. As the stripper carriage reaches its rearrnost position,contact LS2 of switch LS5 in circuit is opened to de-energize the motormagnetic M2-RE- TURN. Contact LS51 in circuit 3 is closed to energizethe magnetic Ml-RAISE of motor M1 to start the upward movement of theelevator to move the next layer of articles to article-strippingposition. While the last layer of boxes is being removed from thepallet, the table T engages switch LS2 to close the contact LS2-2 incircuit 5. Then, when the last row of the last layer of boxes is on thestripper carriage and being moved rearwardly, and switch LS4 is engagedby the stripper during its rearward movement, contact LS4-1 of LS4 incircuit 5 is closed to energize magnetic M1- LOWER, causing the table tobe lowered. Contact Ml-L in circuit 15 opens to de-energize relay B andcontact Ml-L in circuit 3 opens to prevent the energizing of the raisecoil. The stripper carriage opens contact LS5-2 in circuit 10 tode-energize the motor return magnetic MZ-RETURN. In its lowest position,the table engages switch LS3 and opens the contact LS3-1 in circuit 5 tode-energize motor magnetic M1LOWER and to close contact LS3-2 .in thecircuit 7 to energize motor M5 which is the pallet conveyor motor. Theempty pallet is thereby conveyed rearwardly through the machine, and aloaded pallet which has, during the operation of the palletizer, beendeposited by a fork lift truck or the like on the feed-in conveyor C, ismoved into position under the stripper carriage.

While the stripper carriage has been illustrated as having onlyone-positively driven roller, it is within the scope of the presentinvention to positively drive all the rollers of the carriage.Similarly, in certain installations, all the rollers may be frictionallydriven.

From the foregoing description it will be evident that the presentinvention provides a particularly simple depalletizing machine whichremoves articles from a pallet in a unique and efficient manner.

It is within the scope of the present invention to use the transfercarriage TC with other support structures, other control circuits, anddifferent arrangements of the accumulator conveyor, the diverterconveyor and other article handling mechanisms. For the transfercarriage to remove an article from a support, it is necessary only thatthe carriage be moved into engagement with the side wall of the articlewhile the rollers of the carriageare rotated in a direction tofrictionally urge the article upwardly toward the upper surface of thecarriage.

Having thus described the invention, what is claimed as new and desiredto be protected by Letters Patent is:

1. A machine for unloading articles from a pallet load formed oftransversely aligned rows of articles arranged in multi-row layers,comprising a support structure having an elevated frame, an elevatormounted on said structure for receiving a loaded pallet, power meansarranged when activated to raise said elevator to a predeterminedposition wherein the uppermost layer of articles is disposed in ahorizontal plane, a transfer carriage having a plurality of transverselyextending rollers mounted on said platform for movement in saidhorizontal plane in a first direction toward a position superposed abovesaid elevator and in a second direction away from said superposedposition, drive means for moving said carriage toward said position, adriven belt mounted on said platform and disposed in frictionalengagement with selected ones of said rollers when said carriage isspaced from the position above said elevator and in engagement withsubstantially all of said rollers when said carriage is in saidsuperposed position, means for moving said belt in said first directionto rotate the rollers in contact therewith, frictional article engagingmeans carried by the roller nearest the pallet, and control meansassociated with said elevator raising means for deactivating saidelevator raising means when the uppermost layer of articles is elevatedto said predetermined position in the path of movement of said carriageand associated with said carriage drive means for energizing said drivemeans to move said transfer carriage toward the articles on the pallet,said leading roller frictionally engaging the lower end of side wallportions or" the articles and lifting the row of articles onto saidleading roller, whereby the articles are moved onto succeeding rollerswhich convey the articles rearwardly while the carriage is advancedtoward the next transverse row of articles.

2. A machine for unloading successive transverse rows of articles from apallet load formed of transversely aligned rows of articles in layers,comprising means for positioning the uppermost layer of articles withtheir bottom surfaces in a predetermined horizontal plane, a carriagereciprocable in said plane between a forward position and a rearwardposition, a positively driven roller mounted in said carriage and havingfrictional article engaging means, 'a plurality of frictionally drivenrollers mounted in said carriage parallel to said positively drivenroller and said transverse article row, belt means extending normal tosaid rollers and disposed in frictional driving engagement with saidfrictionally driven rollers when said carriage is in its forwardmostposition and engaging selected ones of said rollers when said carriageis in its rearwardmost position, reversible drive means connected tosaid belt means, movement of said belt means in one direction beingeffective to impart a tangential push to said rollers tending to rotatesaid rollers and urge the rollers bodily in a forward direction,resilient means urging said carriage toward said forwardmost position,control means for operating said reversible drive means when theuppermost article layer is positioned in said predetermined plane in thepath of movement of said carriage for moving said belt means in said onedirection to initiate the forward movement of said carriage under theurging of said resilient means, second drive means driven by saidreversible drive means and connected to said driven roller to impart apush to said driven roller tending to rotate said positively drivenroller in a direction to move its upper surface counter to the directionof carriage advance and tending to urge said driven roller bodily towardthe forward end of the machine to assist in moving said carriage forwardin conjunction with said resilient urging means to a position whereinthe friction surface of said positively driven roller engages the lowerend of side Wall portions of the articles of the uppermost layer and byfrictional engagement therewith lifts the row of articles onto saidpositively driven roller and moves the articles rearwardly onto saidfrictionally driven rollers while said carriage is advancing toward thenext transverse row of articles.

3. In an article handling apparatus, a support structure, a transfercarriage mounted for reciprocating movement in said structure between aforward and a rearward position and including a pair of endless chainsand a plurality of rollers rotatably secured between said chains, afirst drive shaft operatively connected in driving engagement to saidcarriage, a spring drive mechanism connected to said first drive shaftto rotate said shaft in a direction to move said carriage to saidforward position, a second drive shaft journalled in said structureadjacent said first drive shaft, a plurality of drive belts connected tosaid second drive shaft to be driven thereby and having frictionsurfaces in engagement with the rotatable rollers of said carriage, auni-directional drive unit connected between said first and second driveshafts, means for rotating said second drive shaft in a direction torotate said first drive shaft through said unidirectional drive unit ina direction to move said carriage to said rearward position against theresistance of said spring mechanisms and means for reversing thedirection of rotation of said second drive shaft to permit said springmechanism to move said carriage to the forward position, saiduni-directional drive unit being adapted to disconnect said drive shaftsduring forward movement of said carriage.

4. In article handling apparatus, a support structure, a strippercarriage mounted for reciprocation in said structure between a forwardand a rearward position and including a flexible frame and a pluralityof rollers mounted for free rotation in said frame, a pallet elevatordisposed in said structure, means for guiding said carriage for movementalong a path having a horizontal portion over said pallet elevator and asubstantially vertical portion alongside said elevator, power meansoperatively connected to said pallet elevator for raising and loweringsaid elevator, control means for activating said power means to movesaid elevator to a position wherein a plurality of articles carried by apallet on said elevator are in the path of movement of the rollers asthe carriage is moved toward its forward positon, and a powerdrivenendless drive member mounted in the upper portion of said supportstructure independently of said flexible carriage and adjacent the pathof said flexible carriage and arranged to drivingly engage theforwardmost roller of said carriage to rotate said roller in a directionto cause the upper surface thereof to move rearwardly, as said carriagemoves forwardly, whereby each article carried by the pallet will becontacted by the forwardmost roller in said carriage and raised andmoved rearwardly over said carriage.

5. In article handling apparatus, a support structure, a transfercarriage mounted for reciprocating movement in said structure between aforward and a rearward position, a first drive shaft journalled in saidstructure and connected in driving relation to said carriage, a springmechanism connected to said first drive shaft to rotate said shaft inadirection to move said carriage to its forward position, a second driveshaft journalled in said structure adjacent said first drive shaft, anoverrunning clutch unit operatively connected between said shafts, andmeans for rotating said second drive shaft in a direction to drive saidfirst shaft through said clutch unit to move said carriage to therearward position against the resistance of said spring mechanism saidclutch permitting said first drive shaft to remain stationary duringmovement of said carriage to forward position.

6. In article handling apparatus, a support structure, a transfercarriage mounted for reciprocating movement in said structure between aforward and a rearward position and including a pair of spaced endlesschains and a plurality of rotatable rollers carried by said chains, apair of shafts journalled in spaced relation in said support structure,a pair of spaced sprockets on each shaft, each sprocket on one shaftbeing aligned in the same plane as a sprocket on the other shaft, eachaligned pair of sprockets being arranged to receive one of said endlesschains, a spring drive mechanism connected to one of said shafts to turnsaid one shaft in a direction to rotate said sprockets and move saidcarriage to its forward position in said support structure, a thirdshaft journalled in said structure adjacent the particular shaft towhich said spring drive mechanism is connected, a unidirectional driveunit operatively connected between said particular shaft and said thirdshaft, and mean-s for rotating said third shaft in a direction to drivesaid particular shaft through said uni-directional drive unit to movesaid carriage to its rearward position.

7. In an article handling apparatus, a support, an elevator mounted forvertical movement in said support and adapted to carry a plurality ofsuperposed articles, an articulated carriage mounted in said support formovement from a forward position wherein a major portion of the carriageis disposed in a horizontal position above said elevator and a rearwardposition wherein a major portion of said carriage is in verticalposition alongside said elevator, means for actuating said elevator toposition the uppermost article on the elevator in the path of movementof the carriage as it moves toward its forward position, rotary means onthe lead-ing edge of said carriage for engaging and lifting the articleas it comes into contact with the article during forward movement ofsaid carriage, means for moving said carriage between said forward andrearward positions, and power-driven endless drive members mounted in anupper portion of said sup port adjacent the path of movement of saidarticulated carriage as said carriage moves toward said forwardposition, each endless drive member having a reach in driving engagementwith said rotary means for rotating said rotary means in a direction tolift the article in contact therewith.

8. A machine for unstacking a palletized load of articles in which thearticles are arranged in layers comprising a support structure, anelevator mounted in said structure for vertical reciprocating movement,means for raising said elevator step-by-step in increments each one ofwhich is equal to the depth of a layer of stacked articles in the load,a carriage mounted in said structure for movement between a forwardposition wherein a major portion of the carriage is disposed ingenerally horizontal position above said elevator and a rearwardposition wherein said carriage is disposed generally verticallyalongside said elevator, rotary means on the forward edge of saidcarriage for engaging and lifting the articles on, the elevator as saidrotary means comes into contact therewith during forward movement ofsaid carriage, means for moving said car-riage between said forward andrearward positions, and power-driven endless drive members mounted in anupper portion of said support adjacent the path of movement of saidarticulated carriage as said carriage moves toward said forward posi- 1l movement of said carriage, a roller mounted on the'forward edge ofsaid carriage and having a friction surface, power means for moving saidcarriage along said path to bring said roller into contact with the sideedges of the articles of the uppermost layer of articles on saidelevator, said power means including a spring mechanism operativelyconnected between said carriage and said support.

10. In an article handling mechanism, a support structure, a flexiblestripper carriage mounted in said structure for movement along apredetermined path between a forward position wherein a major portion ofsaid carriage is disposed in a substantially horizontal plane and arearward position wherein a major portion of said carriage is disposedin a substantially vertical plane, means for positioning articles in thepath of forward movement of said carriage means on the forward edge ofsaid carriage for engaging the side edge of each article and raising itonto the upper surface of said carriage during continued forwardmovement of said carriage, and means for moving said carriage betweensaid forward and rearward posit-ions including a spring mechanism urgingsaid carriage in a forward direction to resiliently urge the articlegripping means on the carriage into cont-act with the articles.

11. In an article handling mechanism, a support structure, a flexiblestripper carriage mounted in said structure for movemment along apredetermined path between a forward position wherein a major portion ofsaid carriage is disposed in a substantially horizontal plane and arearward position wherein a major portion of said carriage is disposedin a substantially vertical plane, means for positioning articles in thepath of forward movement of said carriage, means on the forward edge ofsaid carriage for engaging the side edge of each article and raising itonto the upper surface of said carriage during continued forwardmovement of said carriage, and means for moving said carriage betweensaid forward and rearward positions, including a spring mechanismoperatively connected to said carriage for urging said carriage to saidforward position, and a uni-directional drive unit for urging saidcarriage to said rearward position against the resistance of said springmechanism.

12. In an article handling mechanism, a support structure, a flexiblestripper carriage including a plurality of transverse rollers mounted insaid structure for movement along a predetermined path between a forwardposition wherein a major portion of said carriage is disposed in asubstantially horizontal plane and a rearward position wherein a majorportion of said carriage is dis- .posed in a substantially verticalplane, means for positioning articles in the path of forward movement ofsaid carriage, means on the forward roller of said can riage forengaging the side edge of each article and raising it onto the uppersurface of said carriage during continued forward movement of saidcarriage, means for moving said carriage between said forward andrearward positions, and endless belt means mounted in said supportstructure and having a generally horizontal reach adjacent the path ofmovement of said carriage to engage the rollers of said carriage infrictional driving engagement as said carriage moves toward said forwardposition.

13. In an article handling apparatus, a support, an elevator mounted forvertical movement in said support and adapted to carry a plurality ofsuperposed articles, an articlulated carriage mounted in said supportfor movement from a forward position wherein a major portion of thecarriage is disposed in a horizontal position above said elevator and arearward position wherein a major portion of said carriage is invertical position alongside said elevator, said carriage comprising aplura-lity of spaced transverse rollers, means for actuating saidelevator to position the uppermost article on the elevator in the pathof movement of the carriage as it .moves toward its forward position,means on the leading .roller of said carriage for engaging and liftingthe article as said roller comes into contact with the article duringforward movement of said carriage, means for moving said carriagebetween said forward and rearward positions, and endless drive membersmounted in said support structure independently of said carriage andadjacent the path of movement of said carriage as it moves toward saidforward position, each endless drive member having a reach arranged toengage and drive at least one of the rollers of said carriage.

14. In an article handling apparatus, a support, an elevator mounted forvertical movement in said support and adapted to carry a plurality ofsuperposed articles, an articulated carriage mounted in said support formovement from a forward position wherein a major portion .of thecarriage is disposed in a horizontal position above said elevator and arearward position wherein a major portion o'fsaid carriage is invertical position alongside said elevator, said carriage comprising aplurality of spaced transverse rollers, means for actuating saidelevator to position the uppermost article on the elevator in the pathof movement of the carriage as it moves toward its forward position,mean on the'leading roller of said carriage for engaging, and liftingthe article as said roller comes into contact with the article duringforward movement of said carriage, means for moving said carriagebetween said forward and rearward positions, and endless drive membersmounted in said support structure independently of said carriage andadjacent the path of movement of said carriage as it moves toward saidforward position, said drive members including chains for positivelydriving said leading roller and friction belts for driving the rollerstrailing said leading MA RVIN A. CHAMPION, Primary Examiner.

MORRIS TEMIN, HUGO O. SCHULZ, GERALD M.

FORLENZA, Examiners.

1. A MACHINE FOR UNLOADING ARTICLES FROM A PALLET LOAD FORMED OFTRANSVERSELY ALIGNED ROWS ARTICLES ARRANGED IN MULTI-ROW LAYERS,COMPRISING A SUPPORT STRUCTURE HAVING AN ELEVATED FRAME, AN ELEVATORMOUNTED ON SAID STRUCTURE FOR RECEIVING A LOADED PALLET, POWER MEANSARRANGED WHEN ACTIVATED TO RAISE SAID ELEVATOR TO A PREDETERMINEDPOSITION WHEREIN THE UPPERMOST LAYER OF ARTICLES IS DISPOSED IN AHORIZONTAL PLANE, A TRANSFER CARRIAGE HAVING A PLURALITY OF TRANSVERSELYEXTENDING ROLLERS MOUNTED ON SAID PLATFORM FOR MOVEMENT IN SAIDHORIZONTAL PLANE IN A FIRST DIRECTION TOWARD A POSITION SUPERPOSED ABOVESAID ELEVATOR AND IN A SECOND DIRECTION AWAY FROM SAID SUPERPOSEDPOSITION, DRIVE MEANS FOR MOVING SAID CARRIAGE TOWARD SAID POSITION, ADRIVEN BELT MOUNTED ON SAID PLATFORM AND DISPOSED IN FRICTIONALENGAGEMENT WITH SELECTED ONES OF SAID ROLLERS WHEN SAID CARRIAGE ISSPACED FROM THE POSITION ABOVE SAID ELEVATOR AND IN ENGAGEMENT WITHSUBSTANTIALLY ALL OF SAID ROLLERS WHEN SAID CARRIAGE IS IN SAIDSUPERPOSED POSITION, MEANS FOR MOVING SAID BELT IN SAID FIRST DIRECTIONTO ROTATE THE ROLLERS IN CONTACT THEREWITH, FRICTIONAL ARTICLE ENGAGINGMEANS CARRIED BY THE ROLLER NEAREST THE PALLET, AND CONTROL MEANSASSOCIATED WITH SAID ELEVATOR RAISING MEANS FOR DEACTIVATING SAIDELEVATOR RAISING MEANS WHEN THE UPPERMOST LAYER OF ARTICLES IS ELEVATEDTO SAID PREDETERMINED POSITION IN THE PATH OF MOVEMENT OF SAID CARRIAGEAND ASSOCIATED WITH SAID CARRIAGE DRIVE MEANS FOR ENERGIZING SAID DRIVEMEANS TO MOVE SAID TRANSFER CARRIAGE TOWARD THE ARTICLES ON THE PALLET,SAID LEADING ROLLER FRICTIONALLY ENGAGING THE LOWER END OF SIDE WALLPORTIONS OF THE ARTICLES AND LIFTING THE ROW OF ARTICLES ONTO SAIDLEADING ROLLER, WHEREBY THE ARTICLES ARE MOVED ONTO SUCCEEDING ROLLERSWHICH CONVEY THE ARTICLES REARWARDLY WHILE THE CARRIAGE IS ADVANCEDTOWARD THE NEXT TRANSVERSE ROW OF ARTICLES.